Ginseng

1Departments of Horticulture, Plant Pathology, and Soil Science, College
of Agricultural and Life Sciences and Cooperative Extension Service, University
of Wisconsin-Madison, WI 53706.2Department of Agronomy and Plant Genetics, Minnesota Extension Service,
University of Minnesota, St. Paul, MN 55108.3Former Marathon County Agricultural Agent, Cooperative Extension Service,
Courthouse, Wausau, WI 54401-5501.

I. History:

American ginseng (Panax quinquefolius, L.) is a perennial herb native to
the deciduous forests of the eastern United States. Wild ginseng once thrived along
most of the nation's eastern seaboard, from Maine to Alabama and west to Michigan,
Wisconsin and Minnesota. It still grows wild, but it was over-harvested in the mid-1970s
and was subsequently defined as an endangered species. Currently, 18 states issue
licenses to export it. In Wisconsin and several other states where ginseng is cultivated,
a permit is not required to export artificially propagated ginseng.

Ginseng was one of the earliest marketable herbs to be harvested in this country.
Wild ginseng was one of Minnesota's first major exports. In 1860, more than 120
tons of dried ginseng roots were shipped from the state to China. American ginseng
is similar to Asian ginseng, Panax ginseng, L., which grows wild in Northern
Manchuria and has been harvested there for thousands of years.

Ginseng is prized in the Orient for its purported curative properties. Based on
an ancient Chinese legend, early emperors proclaimed it a panacea to be ingested
or used in lotions and soaps. The genus name, Panax, is derived from the
Greek "panakeia," which means universal remedy. The term "ginseng" is
derived from the Chinese term "jen-shen," which means "in the image of
a man." Ginseng roots shaped like the human body are considered highly desirable.
In particular, old roots (some may be nearly a century old) are prized because their
longevity is claimed to be transferred to the person who consumes them.

Ginseng root is reputed to lower blood sugar and cholesterol levels, protect against
stress, enhance strength and promote relaxation. Koreans have fed ginseng to race
horses to enhance their performance on the track. Although some European and Asian
studies appear to support some of these claims, American researchers remain skeptical.
Ginseng is not a drug and should not be taken as such. It is classified by the Food
and Drug Administration (FDA) as a "generally recognized safe food" (GRAS).

Ginseng became a domesticated crop in the late 1800s. Attempts to produce the crop
in Wisconsin in the late 1870s failed due to disease. In 1904, the four Fromm brothers
from the Wisconsin township of Hamburg, near Wausau, transplanted 100 wild ginseng
plants from nearby forests onto a plot of their land and carefully duplicated the
natural growth conditions. The perseverance of these early ginseng growers and the
ideal growth conditions in Marathon County have made it the ginseng capital of the
United States, producing approximately 10% of the world's supply of ginseng root.
More than 90% of the cultivated ginseng grown in the United States is grown in Wisconsin,
and 90 to 95% of Wisconsin-grown ginseng is produced in Marathon County.

It is estimated that Wisconsin grew 3,000 to 5,000 acres of ginseng in 1990, and
sales of the root earned almost $70 million for farmers in Marathon County. Most
of Wisconsin's ginseng growers cultivate no more than one acre of the crop annually.
Most of the nation's ginseng crop is exported to Hong Kong, where it enters duty-free.
Much is then redistributed to other locations in the Far East.

Ginseng can be a profitable crop, but it requires an enormous commitment of time,
money and labor for successful commercial production. Ginseng beds in Wisconsin
are usually cultivated for three years before harvest, unless disease problems mandate
earlier harvest.

II. Uses:

In the Far East, ginseng root is used in toothpaste, soft drinks, tea, candy, chewing
gum and cigarettes. It also appears on the market as crystals, extract, powder capsules
and is sold as the whole root. In the United States, ginseng and ginseng products
are marketed in Asian food and health food stores. Most of the ginseng used in the
United States, however, is imported from Korea. The amount of Asian ginseng that
is imported is about equal to the amount of higher-priced American ginseng that
is exported.

Ginseng seed is also marketed. Ginseng plants generally begin to produce harvestable
seed in the third year of growth. It takes approximately 200 plants to produce 1
lb of seed, which may produce 5,000 seedlings.

III. Growth Habits:

American ginseng plants are generally started from seeds. Seedlings or roots for
transplanting are available commercially, but are used infrequently. Seeds are planted
in the fall and germinate in the spring. Although researchers have examined ways
to break this juvenility requirement and hasten germination, it is still not understood.

First-year seedlings produce one compound leaf with three leaflets. This leaf, 1
to 2 in. in height and spread, is the only above-ground growth in the first year.
Underground, the plant develops a thickened root about 1 in. long and up to 3 in.
wide. At the top of the root, a small rhizome or "neck" develops with a regeneration
bud at the apex of the rhizome. In autumn, the leaf drops, and a stem supporting
new leaves emerges from the regeneration bud the following spring.

The plant develops more leaves, with more leaflets, each year until the fourth or
fifth year. A mature plant is 12 to 24 in. tall and has 3 or more leaves, each consisting
of 5 ovate leaflets. Leaflets are approximately 5 in. long and oval-shaped with
serrated edges. In midsummer, the plant produces inconspicuous greenish-yellow clustered
flowers. The mature fruit is a pea-sized crimson berry, generally containing 2 wrinkled
seeds.

After three years of growth, the roots begin to attain a marketable size (3 to 8
in. long by 3 to 1 in. thick) and weight (1 oz). In older plants, the root is usually
forked. Wild or high-quality cultivated ginseng root has prominent circular ridges.
Highest quality mature root breaks with a somewhat soft and waxy fracture. Young
or undersized roots dry hard and glassy and are less marketable.

IV. Environment Requirements:

A. Climate:

Ginseng grows best under conditions that simulate its natural habitat. It requires
70% to 90% natural or artificial shade. Ginseng thrives in a climate with 40 to
50 in. of annual precipitation and an average temperature of 50oF. It
requires several weeks of cold temperatures for adequate dormancy.

B. Soil:

C. Seed Preparation and Germination:

Most ginseng crops are started from seed, rather than roots or seedlings. This is
the least expensive way to start a plantation and may help prevent the introduction
of soil-borne disease to new plantations. Ginseng requires 3 to 5 years to produce
a marketable crop from seed.

As there is an 18 month seed dormancy, freshly harvested seed cannot be used for
starting a crop. It must be stratified for 18 to 22 months before planting. Seed
stratification involves soaking the seed in a formaldehyde solution and in a fungicide,
then burying the seed outdoors in moist sand. Most seed is already stratified when
it is purchased and needs only to be treated with a fungicide and sown. Seed should
not be allowed to dry out before or after seeding. (For detailed instructions on
seed stratification, see "American Ginseng Culture in the Arid Climates of British
Columbia" by Oliver, Van Lierop and Buonassisi).

V. Cultural Practices:

A. Seedbed Preparation:

For planting seeds or seedlings, till the soil to a depth of 8 to 10 in., and remove
rocks. For root planting, work the beds 12 in. deep. For best results, mix soil
1 to 1 with fiber-free woodland soil.

Make beds 4 ft wide with alleys between them for walkways and for farm equipment.
If the bed is on flat ground, mound the center to facilitate good runoff. Slope
the walkways so they will drain water from the beds during heavy rains.

Shade can be provided by wooden lath sheds or polypropylene fabric. Artificial shade
should be placed about 7 ft above the ground to ensure good air circulation. Do
not use burlap or muslin, which can interfere with air circulation. (For more detailed
instructions on how to provide artificial shade, see "American Ginseng Culture in
the Arid Climates of British Columbia" by Oliver, Van Lierop and Buonassisi).

B. Seeding Date:

Ginseng seed is generally planted in the fall and covered with mulch until spring.
It can also be spring-planted, but if seeding is not completed by May 1, the seed
may begin to sprout prematurely.

Roots can be transplanted any time after the tops of the plants have begun to die
back but before the ground has frozen.

C. Method and Rate of Seeding:

Plant seedlings 1/8 to 2 in. deep and 4 in. apart in the row. Space the rows 6 in.
apart across the bed. The recommended seeding rate for a 4 ft wide bed with 2 ft
wide paths between beds is 80 to 100 lb/acre. To keep the seed from drying out,
the beds should be covered immediately with 2 to 3 in. of straw.

Plant roots at a 30o to 45o angle from the vertical, with
the crown of the root 3/4 to 1 in. deep. Cover the bed immediately with 1 to 2 in.
of straw. A 4 to 5 in. layer of mulch is necessary on fall transplants to prevent
heaving in frost. Some of the mulch can be removed in the spring before the first
shoots appear.

Set seedlings 8 in. apart in each direction. Closer spacing tends to increase disease
in the plantation.

D. Fertility and Lime Requirements:

Heavy use of manure or commercial fertilizers lessens the resemblance of cultivated
ginseng to the wild root and hence may reduce marketability. Over-manuring may also
force growth and lower disease resistance. Although little research in ginseng fertility
has been conducted, common practice has been to fertilize as for other root crops.
Recommended rates are about 15 lb P2O5/acre and 60 lb K2O/acre
for soils testing in the optimum range for vegetables (30 to 45 ppm Bray P1
and 140 to 200 ppm soil test K).

Nitrogen needs range from 20 to 60 lb/acre, depending on soil organic matter level.
(However, some growers have been known to use considerably more.) Growers have tended
to use lower-salt fertilizers, such as ammonium sulfate, potassium sulfate and potassium-magnesium
sulfate. Although secondary and/or micronutrients are often involved in fertilization
programs, little research has been conducted to confirm responsiveness.

Some growers fertilize with leaves or old hardwood sawdust or with ground-up rotted
hardwood. Others prefer woodland soil or rotted leaves 4 to 6 in. deep, spaded to
a depth of about 8 in. with fine raw bonemeal (1 lb/sq. yd.) worked in.

Fertilizers should be applied during the dormant season at least a couple of weeks
before plants emerge.

E. Variety Selection:

Although no improved varieties have been developed, American ginseng shows variations
in certain characteristics, particularly in the roots. Plants from the northern
part of the country, particularly Wisconsin and New York, are considered good breeding
stock, because they furnish roots of good size, weight and shape.

F. Weed Control:

Weeds can be controlled mechanically with mulching and hand weeding and chemically
with Fusilade 2000. See Table 1 for instructions on herbicide use.

G. Diseases and Their Control:

Ginseng is susceptible to a number of fungal diseases, including Alternaria leaf
and stem blight, Phytophthora root rot and foliar blight, seedling damping-off caused
by Pythium and Rhizoctonia, rusty root and root knot nematode. Ginseng
gardens that are cultivated in the woods may suffer less from diseases than do plantings
under artificial shade.

To minimize disease problems, select a growing site with good drainage. Good air
circulation is also crucial and can be attained by providing cleared areas (walkways)
around the beds, relatively uncrowded spacing and control of weeds. Thin spacing
also reduces the likelihood of disease spread through foliar or root contact. Wisconsin
growers generally do not reuse a ginseng field for succeeding ginseng crops.

Table 1 shows pesticides labelled for nationwide use on ginseng. The University
of Wisconsin has obtained approval from the Environmental Protection Agency (EPA)
(Sec. 18 and Sec. 24) for several additional fungicides. Approval is granted for
use in Wisconsin only, and use must be reported to the Wisconsin Department of Agriculture.
Consult your local County Extension Agent each year to find out which pesticides
may be applied to ginseng in your area.

H. Insects and Other Predators and Their Control:

Ginseng is sometimes attacked by white grubs and wireworms. Voles and field mice
may feed on the roots. See Table 1 for recommended pesticides.

Table 1. Pesticides labeled for nationwide use on cultivated ginseng as of November
1, 1991.Use only approved materialsâ€¦Follow label directions!

Pest

Materials

Treatment(s)

Restrictions/Comments

ALTERNARIA
Leaf and Stem Blight

TankMix
ROVRAL 50W or ROVRAL 4F (Rhone-Poulenc)

2 lbs/acre and

Best if applied 8 hours before rain. DO NOT apply ROVRAL within 36 hours of harvest.

Apply when grasses are 2-8" tall; before tilling or heading.Direct spray away
from ginseng foliage.
DO NOT apply within 1 year of harvest.
EPA REG NO: 10182-104

All recommendations are in terms of products per acre (not a.i.-active ingredient).
Compiled by Jennifer Parke and Brian Hudelson, University of Wisconsin-Madison.

I. Harvesting:

In Wisconsin, most growers harvest ginseng the third year after planting from seed.
The roots are dug in the fall and vigorously washed to remove surface soil. It is
important to handle the roots carefully to keep the branching forks intact and maintain
the natural color and circular markings.

J. Drying and Storage:

Ginseng roots are dried on wire-netting shelves in a heated, well-ventilated room.
Since overheating destroys color and texture, begin drying the roots at a temperature
between 60o and 80oF for the first few days, then gradually
increase it to about 90oF for three to six weeks. Turn the drying roots
frequently. Store the roots in a dry, airy, rodent-proof container just above freezing.

VI. Yield Potential and Performance Results:

Yields of dried roots from a well-managed planting average about 1 ton/acre, although
greater yields are often reported.

A typical seed yield is 150 to 250 lb/acre.

VII. Economics of Production and Markets:

Ginseng growers typically invest $20,000/acre and 600 hrs of labor annually and
get no return on their investment until the third or fourth year. Seed and shading
materials alone can cost more than $29,000/acre. It may take 10 years to break even.
An average crop might net $30,000/acre, depending on the price, which tends to fluctuate
widely from year to year. Prices for dried roots range from $20 to $45/lb. Seed
sells for $50 to $100/lb.

In Wisconsin, growers are assessed $0.15/lb of dried root for promotion and research,
and the funds are administered by the Ginseng Board of Wisconsin, located in Wausau,
Wisconsin. There are several seed and root suppliers and ginseng buyers in Wisconsin.
For information, contact the Ginseng Board of Wisconsin, or the Wisconsin Ginseng
Growers Association both at 500 3rd St., Suite 208-2, Wausau, Wisconsin 54401 (tele
715-845-7300).

References to pesticide products in this publication are for your convenience and
are not an endorsement of one product over other similar products. You are responsible
for using pesticides according to the manufacturer's current label directions. Follow
directions exactly to protect people and the environment from pesticide exposure.
Failure to do so violates the law.